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MRCOOL DIY 5th Gen 25 Ft. Pre-Charged Quick Connect Line Set, 3/8" x 5/8", for DIY 24K & 36K Indoor Mini Split Air Handler

BY: MRCOOL | SKU: DIY25-3858-O Availability: In Stock
$457.00

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MRCOOL DIY 5th Gen 25 Ft. Pre-Charged Quick Connect Line Set

The MRCOOL DIY 5th Gen 25 Ft. Pre-Charged Quick Connect Line Set offers a reliable, efficient, and user-friendly way to extend or replace the connection between your MRCOOL 24K or 36K BTU indoor mini split air handler and outdoor unit. Pre-charged with R-454B refrigerant, this line set simplifies the installation process by eliminating the need for refrigerant handling or vacuum pumps. It features Quick Connect fittings for tool-free connection and is the perfect choice for shorter-distance installs where 25 feet is just right for a clean, professional finish.


MRCOOL DIY 5th Gen 25 Ft. Pre-Charged Quick Connect Line Set Features

Pre-Charged with R-454B – Comes prefilled and sealed with R-454B refrigerant, ensuring efficiency and reducing install time.

Quick Connect Technology – Uses MRCOOL’s proprietary tool-free fittings for secure, no-vacuum, leak-resistant connections.

Built for Larger Units – Designed for use with 24K and 36K 5th Gen MRCOOL indoor air handlers, delivering the proper refrigerant flow and performance.

25 Ft. Line Set Length – Perfect for installs with moderate distance between air handler and condenser, such as along exterior walls or mid-sized rooms.

Heavy-Duty Construction – Insulated and protected with a UV- and weather-resistant jacket for long-term durability in all climates.

No Special Tools Needed – Ideal for homeowners or installers looking for a simple, clean, and efficient installation solution.


MRCOOL DIY 5th Gen 25 Ft. Pre-Charged Quick Connect Line Set Applications

  • Short-to-moderate installs – Ideal when the distance between indoor and outdoor units is around 25 feet

  • Garage or workshop systems – Suitable for connecting to larger units in enclosed secondary structures

  • First-floor installations – Works well for horizontally aligned indoor/outdoor units in larger rooms

  • Mini split system upgrades – Perfect for replacing damaged or aged line sets with a factory-charged option

  • Accessory for 24K & 36K air handlers – Built to support the capacity and dimensions of larger MRCOOL DIY systems


What’s Included?

  • 25 Ft. Line Set (3/8" x 5/8")

  • Pre-installed Quick Connect fittings


MRCOOL DIY 5th Gen 25 Ft. Pre-Charged Quick Connect Line Set Specifications

Series

5th Gen DIY Line Set - R-454B

Compatible Air Handlers

24K & 36K 5th Gen DIY

Line Set Length

25 ft

Lineset Fitting Type

Quick-Connection

Gross Dimensions

32.09" D x 4.92" H x 32.09" W

Color

White

Color Family

Bronze/Copper Metallic

Refrigerant Type

R-454B

Refrigerant Volume (Oz)

2.12

Liquid Line Size

3/8

Suction Line Size

5/8

Registered Warranty

N/A

Has Batteries

No

Contains Electronics

No

Contains Chemicals

Yes

Contains Aerosol

Yes

Contains Compressed Gas

Yes

Proposition 65 Warning

Yes

Restricted States

GU;PR;VI

Net Weight (Lbs)

14.1

Gross Weight (Lbs)

18.5


Frequently-Asked Questions

Is this compatible with smaller MRCOOL units like 12K or 9K?
No. This line set is designed specifically for 24K and 36K 5th Gen MRCOOL DIY air handlers, which require 3/8" x 5/8" line sizes for correct operation.

Does it come with refrigerant already inside?
Yes. It is factory pre-charged with R-454B refrigerant, sealed and ready for use out of the box with compatible units.

Can I shorten or cut this line set to fit a tighter space?
No. This line set must be used at full length as designed. Altering it would compromise the refrigerant seal and system performance.

Do I need an HVAC professional to install it?
While it is DIY-friendly, users unfamiliar with HVAC work are encouraged to seek help from a professional for proper and safe installation.